--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -2241,6 +2241,9 @@ struct sk_buff *ieee80211_beacon_get_tim
sdata = vif_to_sdata(vif);
+ if (!ieee80211_sdata_running(sdata))
+ goto out;
+
if (tim_offset)
*tim_offset = 0;
if (tim_length)